/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.io.fs;



import com.bff.gaia.unified.sdk.coders.AtomicCoder;

import com.bff.gaia.unified.sdk.coders.Coder;

import com.bff.gaia.unified.sdk.coders.VarIntCoder;

import com.bff.gaia.unified.sdk.coders.VarLongCoder;



import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;



/**

 * A {@link Coder} for {@link MatchResult.Metadata}.

 *

 * <p>The {@link MatchResult.Metadata#lastModifiedMillis()} field was added after this coder was already

 * deployed, so this class decodes a default value for backwards compatibility. See {@link

 * MetadataCoderV2} for retaining timestamp information.

 */

public class MetadataCoder extends AtomicCoder<MatchResult.Metadata> {

  private static final MetadataCoder INSTANCE = new MetadataCoder();

  private static final ResourceIdCoder RESOURCE_ID_CODER = ResourceIdCoder.of();

  private static final VarIntCoder INT_CODER = VarIntCoder.of();

  private static final VarLongCoder LONG_CODER = VarLongCoder.of();



  private MetadataCoder() {}



  /** Returns the singleton {@link MetadataCoder} instance. */

  public static MetadataCoder of() {

    return INSTANCE;

  }



  @Override

  public void encode(MatchResult.Metadata value, OutputStream os) throws IOException {

    RESOURCE_ID_CODER.encode(value.resourceId(), os);

    INT_CODER.encode(value.isReadSeekEfficient() ? 1 : 0, os);

    LONG_CODER.encode(value.sizeBytes(), os);

  }



  @Override

  public MatchResult.Metadata decode(InputStream is) throws IOException {

    return decodeBuilder(is).build();

  }



  MatchResult.Metadata.Builder decodeBuilder(InputStream is) throws IOException {

    ResourceId resourceId = RESOURCE_ID_CODER.decode(is);

    boolean isReadSeekEfficient = INT_CODER.decode(is) == 1;

    long sizeBytes = LONG_CODER.decode(is);

    return MatchResult.Metadata.builder()

        .setResourceId(resourceId)

        .setIsReadSeekEfficient(isReadSeekEfficient)

        .setSizeBytes(sizeBytes);

  }



  @Override

  public boolean consistentWithEquals() {

    return true;

  }

}